System of electrical distribution.



PATENTED AUG. 11, 1908.

APPLICATION FILED JAN. 3, 1908.

I I I IIIMIILJIITI 0 0, Kg 6 W1 r b L f m M E m I ATTORNEY.

JOSEPH LESTERWOODBRIDGE, OF PHILADELPHIA, PENNSYLVANIA.

SYSTEM OF ELECTRICAL DISTRIBUTION.

No. s95,s25.

Specification of Letters Patent.

Patented Aug. 11, 1908.

Application filed January 3, 1908. Serial No. 409,174.

tery is employed to compensate for load fluctuations, and is particularly applicable to systems in which apparatus is provided for gradually varying theaverage load on the generators to follow the average demandof the translating devices so as to avoid continuous charge or discharge of the battery with changes in average load. In such a system the apparatus above described would current will flow in the field winding F.-

act to throw continually increasing load on the generators with an increase. in the average demand without regard to the capacity of the generators to handle such increase, possibly resulting in an excessive overload on the generators. To avoid this possibility I provide means for preventing the controlling apparatus from continuing to throw increased load on the generators after the load of these machines has reached a certain predetermined maximum. This and other objects will be more clearly seen by reference to the following description taken in connection with the accompanying drawing diagrammatically illustrating a system of distribution embodying features of the invention.

In the drawing A and A are the generators supplying current to the circuit 1, 2. A storage battery B, with its suitably driven booster (I is connected across the circuit '1, 2,

and the field F of the booster iscontrolled by the counter-electro motive force exciter E. The exciter E, is connected in series with the field F, the two being connected directly across the circuit 1, 2, and so long as the electro-motive-force of the exciter E, is equal and opposite tothat of the circuit 1, 2, Ifio T e electro-motive-force of the exciter E, is con trolled by its .field winding F, which is connected across a variable portion of a shunt D, in series with conductor 1. The current in the field winding F will, therefore be proportional to the current in the shunt D, and therefore, proportional to the combined output of the generators A and A. When this the tick 1 output has a certainrritical value the current in the field F, will be sullicient to produce an electro-motive-force in the exciter E, equal to that across the circuit 1, 2, and no current will flow through the field F, of the booster. Slight variations of output from the generator A nd A above and below this critical value will vary the electro-motive-force of the exciter E, causing current to flow in the field F, in one direction or the other accordin g to whether the load on the generators is increased ordiminished, and the effect of this current will be to cause the battery to charge anddischarge to compensate for fluctuations of load which may occur, as for example at L.

The critical value of the output from the generators A and A may be varied by varying the ortion of the shunt D across which FF is connected. In the diagram this variation is produced by moving a sliding contact G along the shunt so as to make contact with it at various points. This contact piece G is mounted on a screw J, driven by a motor M. The armature of the motor M, is connected across circuit 1, 2, with a rheostat R in series whereby'a practically constant current is transmittedthrough this armature. The field excitation of the motor M, is the resultant fi'ect of two field windings K and K The winding K, is connected between the conductor 1, and the corresponding battery terminal. When the battery and circuit 1, 2, are of ,the same potential, as is normally the case when the battery is neither charging nor discharging, there will beno current 111 the field K. It, however the battery begins to discharge by reason of the operation of its booster C, the battery voltage will fall below that of the circuit 1, 2, and current will flow through thefield K. This will excite the field in the direction to operate the motor so as to move the con tact piece G toward the left, thus cutting out a ortion of the shunt I). A greater output wi 1 be required from the generators A and A to produce the re uisite voltage'in the exciter E and the resdlt will bean'increase in output from the generators which will relieve the battery from a portion of its discharge. By pro er design. of the apparatus the effect above escribed may be madeto take place very slowly, so that the change in load on the enerators will be radual, The second field I 2 on the motor M: is connected between the middle point of the batteryand a rheostat R,

which latter is connected across the battery terminals. By this means the current in the ranged to deliver andweceive energy to and from the circuit, electro-responsive means field K may be varied from zero to a certain l for controlling the charge and discharge of the maximum in either direction. winding K may therefore be used to balance the field windin K with any desired difference of voltage between the battery and the circuit 1, 2, thus providing means for producing a net average char 'e or discharge of the battery, as well as a bafance between the charge and discharge. On. the shaft of the motor M, is shown a ratchet wheel H. A pawl S, carried on a pivoted arm P, is arranged to engage the teeth'of the ratchet wheel, when the opposite end of the arm P, is drawn down by the electro-magnet Q. This electro-magnet is energized by relays in the generator circuits. These relays consist of electro-magnets I and I opposed by adjustable springs O and and operating contacts T and T The electro-magnets Pand 1,

are energized by coils in the corres onding.

generator leads; .so that when the oad on either generator reaches a predetermined amount, the-contact will be made and the coil of the electro-magnet Q, will be connected across the circuit 1, 2, thus moving the arm P so that the pawl S, will'engage with the teeth of the ratchet wheel H. This will revent the motor M, from turning inthe irection to cut out additional portions of the shunt D, but will leave it free to turn in the op osite direction in case the load at L, should fall off and the battery begin to charge. The pawl S, on the arm shown is cushioned by a s ring to from stopping the motor lVl too sud P, as here prevent it enly. A

fan N, is mounted on the shaft of the motor to prevent it speed.

The system shown on the diagram and described above, therefore, provides storage battery controllin apparatus adapted to throw momentary uctuations of load on the battery while at the same time the slower changes .of the average load are gradually transferred to thegenerators up to a (point where these are giving a certain pre etermined output when further transfer of load to these machines is prevented.

What I claim is:

1. A system of electrical distribution provided with an automatic regulating apparatus responsive to rapid fluctuations from any average load and also to sustain changes constituting different average loads, and including a storage battery operatively arranged to receive rapid fluctuations, a generator operatively arranged to receive the sustained changes, and means for limiting the described actionof the regulating apparatus toprevent overloading the generators, substantially as described.

2. In combination, an electric circuit and its source, a storage battery operatively arfrom reaching an excessive This field l battery,

other slower acting automatic means adapted to counteract the effects of the first, and means for checking the operation of the last named means when the output from the source reaches a-predetermined value;

3. In combination an electric circuit and its source, a storage battery operatively arranged to deliver and receive energy to and from the circuit, means responsive to de artures from a certain electrical condition of the circuit and adapted to control the battery charge and discharge, slower acting means responsive to changes'of battery conditionand adapted to counteract the effects of the first named means, and means responsive to load on the source for controlling the slower actin means.

4. n combination, an electric circuit and its load, a generator and a storage battery operatively arranged with respect tov the circuit, ap )aratus for controlling the division of load etween the generator and the battery, and means for checking the operation of the controllingapparatus to prevent furits load, a generator and a storage battery operatively arrangedwith respect to the circuit, apparatus for controlling the division of load between the generator and the battery and adapted automatically to transfer load from battery to generator, and means for preventing such transfer after the load on the generator reaches a certain value.

6. In combination an electric circuit and its source, a storage battery in operative relation to the circuit, controlling a paratus including an appropriate field coil ror causing the battery to charge and discharge, connections .from the field coil to the circuit, a counter-electro-motive-force exciter connected in series between the field coil and the circuit, means for exciting the fields of the ex citer by current proportion to the load on the source, and. means responsive to changes of battery condition for varying said proportion.

'7. In combination an electric circuit and its source, a storage battery in operative relation to the circuit, controlling a aratus including an appropriate fieldcoil fbr causing the battery to charge and discharge, connections from the field coil to the circuit, a counter-electro-motive-force exciter connected in series between the field coil and the circuit, means for exciting the fields of the exciter by current proportional to the load on the source, and automatic means for varying said proportion.

8. In combination arr-electric circuit anditssource, a storage batteryin operative-relacliidmg a booster and its field for causing the battery to charge and discharge, conne'ctions from the booster field coil to the circuit,

a counter-electro-motive-force ex'citer conbetween the booster field nected, in series coil'and the circuit, a field coil on the exciter connected across movable contact for varying the resistance of the shunt, a motor for moving said-contact,

condition for operating said motor, v

9. In combination an electric generator and a storage battery connected in "parallel relation, battery'- controlling apparatus in-i eluding a device adapted to lncre'ase and degenerator output by varying the crease the battery. current, a motor for operating said device, and means to prevent the motor from operating to increase the generator output after said output exceeds'a certain limit.

10. In combination an electric generator and a storage battery connected in parallel relation, battery controlling apparatus ina shunt in the circuit, a

I In presence eluding a device adapted to increase and decrease the generator output by varying the battery current, a motor for operating salcl device, and operating in the direction to increase the generator output after said output exceedsa certain value While permitting .it to operate in the op osite direction.

11. n combination an electric circuit and -.its source, a storage battery operatively ar- 'ranged to deliver and means responsive to changes of battery; f

and receive energy to and rom the-circuit, electro-responsive means for controlling the charge and discharge of the battery, otherslower actin automatic means adapted to counteract t e eflects of means to prevent the motor fromthe first,v and-a device for permitting the slower acting imeans to operate in only one direction when the output from on one side of a certain value. In testimony whereof I have hereunto signed my name. v

' JiQSEPH" LESTER WOODBRIDGE.

WILLIAM J. JACKSON,

FRANK E. FRENCH.

the source is 

